Design, simulation and experimental study of a force observer for a flying–perching quadrotor

Abstract

It is significant to know the information of the contact force for the control of the flying–perching quadrotor when it is switching from flying state to perching state. The triaxial force sensor is not only difficult to install but also increases the weight and cost of the flying–perching quadrotor. To overcome these limits, this paper presents a force observer to estimate the contact force. We first build a detailed model of the flying–perching quadrotor in free space and when it gets into contact with the perching surface. The model is modified by considering the proximity effect. According to the model, a force observer was proposed. To demonstrate the performance of the proposed observer, simulations are carried out in ideal environment and with consideration of sensor noises. Moreover, we built an experimental platform and carried out experiments to verify the effectiveness of the designed observer in practical situations.